The Yeti Airlines plane crash in Nepal — which killed all 72 people on board, including a Sydney teacher — has raised questions about the safety of flying in other countries frequently visited by Australians.
Back in 2013, the European Union banned all 20 Nepalese airlines — including Yeti Airlines — from flying to the European Union.
It implemented the ban after the UN's International Civil Aviation Organization (ICAO) raised concerns about safety standards, which all member nations have to follow.
Some other countries that are frequently visited by Australian tourists have also faced scrutiny for their aviation safety records.
Civil aviation authorities in ICAO member states, such as Nepal, have an obligation to oversee safety across their aviation sectors.
According to RMIT University's associate professor of aerospace engineering and aviation, Chrystal Zhang, that means governments need to ensure there are laws and operational standards in place so that their national aviation industries are safe.
Dr Zhang told the ABC that — in addition to regulations introduced by governments — airlines and airports must develop their own safety management systems.
"That can be very broad, covering every element of the operation across the airline, from the personnel, the licensing management, to the maintenance, to daily operation to operational manuals," Dr Zhang said.
She said those standards have to be maintained on an ongoing basis for it to be effective.
What countries and airlines have questionable safety records?
The EU's Air Safety List — which details all airlines banned in the 27-member bloc — provides the clearest indication of which countries and airlines are unsafe, according to Dr Zhang.
There are aircraft from 21 countries, mostly from Africa, on the list of banned airlines.
Commercial planes from Venezuela, Suriname, Iran, Iraq, Zimbabwe, Afghanistan, Angola, Armenia, Congo, Democratic Republic of Congo, Djibouti, Equatorial Guinea, Eritrea, Kyrgyzstan, Liberia, Libya, Nepal, Russia, Sao Tome and Principe, Sierra Leone and Sudan made the EU's list.
Iran Air and North Korea's Air Koryo are subject to operational restrictions in the EU.
Dr Zhang said the EU only blacklists countries if it is not confident with the oversight capability of a nation's civil aviation regulator.
If a nation's aviation sector is deemed unsafe, the EU can ban all registered airlines from that country until improvements are made.
The same can be applied to individual airlines.
"It's one of the very reliable resources that people can refer to … and they constantly update the list," she said.
Several countries and airlines in destinations popular with Australians have been placed on the list but have since been removed.
All 51 Indonesian airlines were banned from flying to the EU in 2007, including national carrier Garuda, because of declining safety standards.
The ban on Indonesian carriers was lifted in 2018.
There have been at least two fatal commercial plane crashes in Indonesia since 2018, including Lion Air flight 610 and Sriwijaya Air flight 182 — both Indonesian airliners that crashed into the Java Sea.
Airline consultant Neil Hansford told the ABC that Indonesia's aviation safety record has improved, mostly because international carriers are flying in from elsewhere, forcing local airlines to improve safety standards.
"Indonesia was a place you wouldn't want to be. It's not in that status [anymore]," he said.
Mr Hansford said the same applied to Thailand, which the US Federal Aviation Administration's (FAA) International Aviation Safety Assessment program found — in November 2022 — did not provide adequate safety oversight that met ICAO standards.
"The good thing is you can get reliable Australian carriers … flying into those countries with all of the disciplines you'd expect of an Australian carrier."
There were three fatal commercial jet incidents in Thailand between 2001 and 2009, inlcuding Bangkok Airways flight 266, One-Two-GO Airlines flight 269 and Thai Airways flight 114, which was rocked by an explosion.
"They've lifted their standards because, if an airport is basically unsafe, the Australian regulator in conjunction with the airlines, won't operate to those sorts of places," Mr Hansford said.
The FAA also found authorities in Bangladesh, Mexico, Pakistan and the Organization of Caribbean States didn't provide adequate safety oversight.
Philippines Airlines was blacklisted by the EU, but was removed from the list in 2015, after the EU determined that the country's civil aviation authority could monitor compliance.
The number one destination for Australian travellers, New Zealand, has some terrain and flying condition similar to Nepal's.
In a sign of stronger aviation safety regulations and enforcement there, pilots flying to mountainous Queenstown on New Zealand's South Island have to undertake special training to land and take off from the airport.
Mr Hansford said pilots were checked regularly and the airport's operators placed a "special focus" on making it safe.
Why are some countries worse than others?
Dr Zhang said while all 193 ICAO member states sign up to follow the same rules, it's ultimately up to the individual states to implement those standards.
She said there were some standards that were compulsory for states to enact, while others were recommended practices and ultimately up to individual members.
Even if the standards were enacted, she said, some governments do not have the financial resources, people or systems to enforce the laws.
She said some countries interpreted the language of ICAO's standards differently, or might think that some guidelines don't apply to them.
"If you have the resources and you have the capacity, like Australia [to implement the standards], we are very famous for our strict regulations," she said.
"But, for other countries … perhaps they are struggling with the resources to not only implement the standards — the technical requirements — but a lack of resources to implement those recommended practices."
Dr Zhang said there was a link between increasing private investment to meet travel demand and safety, particularly in the Asia-Pacific region.
She said governments in the region were having to balance private investment into the airline sector with safety and ensuring there was the appropriate infrastructure in place.
How can Australians fly safely overseas?
For Australians looking to travel overseas and fly safely, Mr Hansford said people should check an airline's safety record and avoid always going for the cheapest option.
"To save $100, [customers] would take a carrier that is not Australian … without any thought as to their safety," she said.
"When you say to people, 'Well, do you think your life is worth $100?' they don't give it a second thought."
He said customers should look at how long the airline has been in operation, and suggested searching websites such as Airline Ratings for tips on which airlines are safest.
Dr Zhang said the EU Air Safety List was a reliable way to check if the airline you will fly with — or country you are travelling to — has a good safety record.
She said the Australian Transport Safety Bureau (ATSB) and the US FAA both publish data about aviation accidents in their respective countries, and suggested that passengers fly with established, well-managed airlines.
"Check the history of the airline, the type of aircraft they are using for flying that particular route," she said.
"The fleet information, I think, is very helpful for the passenger to determine the particular flight they've booked into."
